Swiss biotechnology company Actelion presented mixed trial results for its antibiotic hopeful cadazolid, saying it met the main goal of one late-stage study but failed to hit the target in a second, identical study. Cadazolid, being tested against tough-to-treat Clostridium difficile-associated diarrhoea, is among assets being purchased by Johnson & Johnson as part of the U.S. healthcare giant’s $30 billion takeover of Actelion.

Actelion said the investigational drug met its primary endpoint – resolution of diarrhoea and no further need for therapy on study treatment, maintained for two days after treatment – in its pivotal IMPACT 1 study, but fell short of the same endpoint in its IMPACT 2 study. The company was silent on the future of the drug.

The Swiss company, which said cadazolid demonstrated an acceptable tolerability and safety profile, now plans to analyze the full study results and make them available at upcoming congresses and in peer-reviewed publications.